//public class 人 {
//    public static void main(String[] args) {
//    person p1 =new person();
//    p1.name="yzy";
//    p1.age=18;
//    chind c1 = new chind();
//    c1.name="wly";
//    c1.age=20;
//    }
//}
////class person{
////    String name;
////    int age;
////    person(){
////        System.out.println("这是人");
////    }
////}
//////extends 继承父类
////class chind extends person{
////    String name;
////    int age;
////    chind(){
////        System.out.println("这是小孩");
////    }
////}